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实验二语法分析算符优先分析程序一．实验要求⑴选择最有代表性的语法分析方法算符优先法；⑵选择对各种常见程序语言都用的语法结构，如赋值语句（尤指表达式）作为分析对象，并且与所选语法分析方法要比较贴切。⑶实习时间为6学时。二．实验内容及要求（1）根据给定文法，先求出FirstVt和LastVt集合，构造算符优先关系表（要求算符优先关系表输出到屏幕或者输出到文件）；（2）根据算法和优先关系表分析给定表达式是否是该文法识别的正确的算术表达式（要求输出归约过程）（3）给定表达式文法为：G(E’):E’→#E#E→E+T|TT→T*F|FF→(E)|i(4)分析的句子为:(i+i)*i和i+i)*i三.实验代码#includestdafx.h#includestdio.h#includestdlib.h#includeiostream.hintk;chara;intj;charq;intr;intr1;charst[10][30];chardata[20][20];chars[100];charlable[20];charinput[100];charstring[20][10];charfirst[10][10];charlast[10][10];intfflag[10]={0};intlflag[10]={0};intdeal();intzhongjie(charc);intxiabiao(charc);voidout(intj,intk,char*s);voidfirstvt(charc);voidlastvt(charc);voidtable();voidmain(){inti,j,k=0;printf(请输入文法规则数：);scanf(%d,&r);printf(请输入文法规则：\n);for(i=0;ir;i++){scanf(%s,st[i]);first[i][0]=0;last[i][0]=0;}for(i=0;ir;i++){for(j=0;st[i][j]!='\0';j++){if(st[i][0]'A'||st[i][0]'Z'){printf(不是算符文法!\n);exit(-1);}if(st[i][j]='A'&&st[i][j]='Z'){if(st[i][j+1]='A'&&st[i][j+1]='Z'){printf(不是算符文法!\n);exit(-1);}}}}for(i=0;ir;i++){for(j=0;st[i][j]!='\0';j++){if((st[i][j]'A'||st[i][j]'Z')&&st[i][j]!='-'&&st[i][j]!=''&&st[i][j]!='|')lable[k++]=st[i][j];}}lable[k]='#';lable[k+1]='\0';table();//输出每个非终结符的FIRSTVT集printf(每个非终结符的FIRSTVT集为：\n);for(i=0;ir;i++){printf(%c:,st[i][0]);for(j=0;jfirst[i][0];j++){printf(%c,first[i][j+1]);}printf(\n);}//输出每个非终结符的LASTVT集printf(每个非终结符的LASTVT集为：\n);for(i=0;ir;i++){printf(%c:,st[i][0]);for(j=0;jlast[i][0];j++){printf(%c,last[i][j+1]);}printf(\n);}printf(算符优先分析表如下:\n);for(i=0;lable[i]!='\0';i++)printf(\t%c,lable[i]);printf(\n);for(i=0;ik+1;i++){printf(%c\t,lable[i]);for(j=0;jk+1;j++){printf(%c\t,data[i][j]);}printf(\n);}printf(请输入文法输入符号串以#结束:);scanf(%s,input);deal();}voidtable(){chartext[20][10];inti,j,k,t,l,x=0,y=0;intm,n;x=0;for(i=0;ir;i++){firstvt(st[i][0]);lastvt(st[i][0]);}for(i=0;ir;i++){text[x][y]=st[i][0];y++;for(j=1;st[i][j]!='\0';j++){if(st[i][j]=='|'){text[x][y]='\0';x++;y=0;text[x][y]=st[i][0];y++;text[x][y++]='-';text[x][y++]='';}else{text[x][y]=st[i][j];y++;}}text[x][y]='\0';x++;y=0;}r1=x;//输出转化后的文法规则串printf(转化后的文法为:\n);for(i=0;ix;i++){printf(%s\n,text[i]);}for(i=0;ix;i++){string[i][0]=text[i][0];for(j=3,l=1;text[i][j]!='\0';j++,l++)string[i][l]=text[i][j];string[i][l]='\0';}for(i=0;ix;i++){for(j=1;text[i][j+1]!='\0';j++){if(zhongjie(text[i][j])&&zhongjie(text[i][j+1])){m=xiabiao(text[i][j]);n=xiabiao(text[i][j+1]);data[m][n]='=';}if(text[i][j+2]!='\0'&&zhongjie(text[i][j])&&zhongjie(text[i][j+2])&&!zhongjie(text[i][j+1])){m=xiabiao(text[i][j]);n=xiabiao(text[i][j+2]);data[m][n]='=';}if(zhongjie(text[i][j])&&!zhongjie(text[i][j+1])){for(k=0;kr;k++){if(st[k][0]==text[i][j+1])break;}m=xiabiao(text[i][j]);for(t=0;tfirst[k][0];t++){n=xiabiao(first[k][t+1]);data[m][n]='';}}if(!zhongjie(text[i][j])&&zhongjie(text[i][j+1])){for(k=0;kr;k++){if(st[k][0]==text[i][j])break;}n=xiabiao(text[i][j+1]);for(t=0;tlast[k][0];t++){m=xiabiao(last[k][t+1]);data[m][n]='';}}}}m=xiabiao('#');for(t=0;tfirst[0][0];t++){n=xiabiao(first[0][t+1]);data[m][n]='';}n=xiabiao('#');for(t=0;tlast[0][0];t++){m=xiabiao(last[0][t+1]);data[m][n]='';}data[n][n]='=';}//求FIRSTVT集voidfirstvt(charc){inti,j,k,m,n;for(i=0;ir;i++){if(st[i][0]==c)break;}if(fflag[i]==0){n=first[i][0]+1;m=0;do{if(m==2||st[i][m]=='|'){if(zhongjie(st[i][m+1])){first[i][n]=st[i][m+1];n++;}else{if(zhongjie(st[i][m+2])){first[i][n]=st[i][m+2];n++;}if(st[i][m+1]!=c){firstvt(st[i][m+1]);for(j=0;jr;j++){if(st[j][0]==st[i][m+1])break;}for(k=0;kfirst[j][0];k++){intt;for(t=0;tn;t++){if(first[i][t]==first[j][k+1])break;}if(t==n){first[i][n]=first[j][k+1];n++;}}}}}m++;}while(st[i][m]!='\0');first[i][n]='\0';first[i][0]=--n;fflag[i]=1;}}//求LASTVT集{voidlastvt(charc)inti,j,k,m,n;for(i=0;ir;i++){if(st[i][0]==c)break;}if(lflag[i]==0){n=last[i][0]+1;m=0;do{if(st[i][m+1]=='\0'||st[i][m+1]=='|'){if(zhongjie(st[i][m])){last[i][n]=st[i][m];n++;}else{if(zhongjie(st[i][m-1])){last[i][n]=st[i][m-1];n++;}if(st[i][m]!=c){lastvt(st[i][m]);for(j=0;jr;j++){if(st[j][0]==st[i][m])break;}for(k=0;klast[j][0];k++){intt;for(t=0;tn;t++){if(last[i][t]==last[j][k+1])break;}if(t==n){last[i][n]=last[j][k+1];n++;}}}}}m++;}while(st[i][m]!='\0');last[i][n]='\0';last[i][0]=--n;lflag[i]=1;}}intdeal(){inti,j;intx,y;intz;k=1;s[k]='#';for(i=0;input[i]!='\0';i++);z=i--;i=0;while((a=input[i])!='\0'){if(zhongjie(s[k]))j=k;elsej=k-1;x=xiabiao(s[j]);y=xiabiao(a);if(data[x][y]==''){out(1,k,s);printf(%c,a);out(i+1,z,input);printf(规约\n);do{q=s[j];if(zhongjie(s[j-1]))j=j-1;elsej=j-2;x=xiabiao(s[j]);y=xiabiao(q);}while(data[x][y]!='');intm,n,N;for(m=j+1;m=k;m++){for(N=0;Nr1;N++)for(n=1;string[N][n]!='\0';n++){if(!zhongjie(s[m])&&!zhongjie(string[N][n])){if(zhongjie(s[m+1])&&zhongjie(string[N][n+1])&&s[m+1]==string[N][n+1]){s[j+1]=string[N][0];break;}}elseif(zhongjie(s[m]))if(s[m]==string[N][n]){s[j+1]=string[N][0];break;}}}k=j+1;if(k==2&&a=='#'){out(1,k,s);printf(%c,a);out(i+1,z,input);printf(结束\n);printf(输入串符合文法的定义！\n);return1;}}elseif(data[x][y]==''||data[x][y]==